Stitching mechanism



Feb. l0,` 1942. H. G. BAILEY la'rAl.

sTI'rcHING ywuschmNIsM Filed Aug. 20, 1938 3 Sheets-Sheet l 33 u BY h AEYS.

Feb. l0, 1942.

H. G.- BAILEY ETAL I STITCHING MECHANISM Filed Aug. 20, 1938 3 Sheets-Sheet 2 B 'l w Wcfaggs Amie Patented Feb. 10, 1942 STITCHING MECHANISM Harold G. Bailey and Weston C. Jones, Newark, Ohio, assignors, by mesne assignments, to Qwensn-Corning Fiberglas Corporation, a corporation of Delaware 3' Claims. i The present invention relates to a stitching mechanism especially adapted for stitching thick material such as compressible or resilient'heat insulation blankets having thicknesses more generally about two to six inches thick, more or less as desired.

Heretofore, when stitching thick blankets with the conventional sewing machines using a single thread chain stitch, a lock stitch or the double thread chain stitch as used by a Norwood stitcher, the progress of the needle through the blanket may cause the stitches already formed to pull down and unduly compress the blanket at the stitches. Thus, if a resilient blanket is being stitched, the thicknss of -the blanket at the stitches may be considerably less than the norlmal thickness, and the cross-section of a blanket taken across the rows of stitches may be one of undulating contours. Suchblankets which are pulled downto smaller dimensions at the stitches cannot properly ll a heat insulating space, and

as'aresult, the heat insulating properties of the blanket are materially. decreased.

It is an object of the present invention to provide a stitching mechanism, particularly adapted for thicker types of blankets which will enable a blanket to retain a substantially xed predetermined dimension throughout its surface including the points where the stitches are located.

Such a mechanism we have termed a loose stitching mechanism. v 4 l Another object of the invention is to sew a blanket havinga thickness greater than the distance between the bed plateand presser foot of the stitching mechanism. Often this latter distance at its maximum is about three inches and yet it is desired to sew a six inch blanket and have the thread fed in exactly the proper amount to permit the blanket to expand to the desired six inch thickness.

Another object of the present invention is to provide a loose stitching mechanism which'will not break or jerk the thread or pull uneven loops as it is in operation.

Another object of the present invention .is to provide a loose stitching mechanism operable at high speed. Y Another object of the present' invention is to provide a loose stitching mechanism which, whileVv Application August 20, 1938, Serial No. 225,942

mechanism` which is simple and easy in operation,

which can be assembledland taken downquickly and with minimum effort, and which can be adjusted for different types and sizes of blankets which are to be stitched.. y

Other objects and advantages will become apparent from the following vdescription taken in conjunction'with the drawings, in which:

Fig. 1 is a fragmentary plan view of a stitching mechanism incorporating the present invention;

Fig. 2 is a diagrammatic elevational cross-sec-v tional view of our novelapparatus;

Fig. 3 is a cross-sectional elevationalldetailed view of a finger bar and slide;v

Figs. 4 to 11 inclusive are diagrammatic views of the stitching element illustrating the mechanism for forming the stitches and causing the successive loops to be retained in drawn-.out positions so that a loose stitched blanket may be produced j 'and v Fig. 12 is an elevational cross-sectional view of the stitching mechanism showing a series of stitches more or less diagrammatically.

Referring now more particularly to Figs. 1 to 3, a mat or blanket or other suitable work 20 is carried tothe stitching mechanism on a belt 2|.

` with a series of slots registering with the slots forming each stitch, will, if desired, hold the loops oi more than one of the preceding stitches -a manner to prevent one loop from taking up' the slack of a prior loop.

Another object of the invention is to provide a 'I'he work may have an outer cover 22`of paper,

cloth, metal foil or the like, and if desired, a top cover 23 of similar material. The `top cover may be fed in from a spool 24 and guided over' rolls 25 and 26 to the top of the work 20.

' The work 20 then is passed between a base plate 30 and a presser foot 3|, Where itis stitched.

It is thendrawn out by the caterpillar conveyors `33 and 34 Working in conjunction with one anl other. n

The presser foot 3L isaprovided with a series of slotsY 35 for receiving a series of reciprocating needlesA 36 mounted upon a needle arm 3l over the machine. Thebase plate 30 is also provided 35, also for receiving the .needles 36 as they pass downthrough the mat and coact `witha series of loopers 4I pivoted upon a reciprocating and oscillating arm 42. l

The operation of the needles 36 and looper` 4I is similar to that of a conventional chain stitching mechineemp'loying a d ouble thread chain stitch and hence need not be described more in detail.

I'he`present invention is directed more particularly to the provision7 of a series of reciproeating ngers 45, one'for each vneedle 36. The

fingers are all arranged to extend longitudinally of the work and are mounted upon a finger bar 46 extending transversely of the work and sliding in finger bar slides 41 which are mounted on the upper side of the presser foot 3| (see Fig. 3). These fingers 45 are adapted to move back or forth across the slots 35 in the presser foot under their respective needles when the latter are in their'topmost position. o

The mechanism for reciprocating the finger bar 46 is shown more particularly in Fig. 1. At one end of the finger bar 46 is vmounted a ball 50 which fits in a bifurcated clamp or socket 5|,` .forming a ball and socket joint between the nger bar 46 and a pitman 52. The other end of the pitman 52 is securedv to a pitman strap 53 by means of a pin 54 in order to .permit free vertical swinging movement of the pitman 52. 'I'he pitman strap 53 is bolted to a pivot beam 55 by means of a pivot stud and bolt 56.

The pivot beam 55 is fulcrumed upon a beam stud 60 securedto a frame plate 6|. A series of openings 62 are'provided along the length of the pivot beam 55 through any one of which the pivot stud 60 passes in order to adjust the amount of leverage and length of travel imparted to the pitman 52 and the finger bar 46. The frame plate 6| is also provided with a series of openings 63 into which the pivot stud 60 may be secured according to the desired location of the fulcrum point for the lever beam 55. The openings 62 and 63 are preferably in register with one another when the pivot beam 55 is in center position so that any pair of registering openings may be used without shifting the beam endwise.

n the opposite end of the lever beam 55 is an actuating means comprising a cylindrical cam 65 having a cam track 66 in which rides a cam follower 61. The cam follower 61 may be secured to the lever beam 55 by means of a s tud 68. The cylindrical cam 65 is mounted upon a shaft 63 riding in bearings 10 and actuated by a sprocket wheel 1| and chain 12. The chain 12 may be, driven synchronously with the sewing machine mechanism and preferably by the same drive as the sewing machine.

The cylindrical cam 65 imparts an oscillating movement to the pivot-beam 55 which in turn `imparts a reciprocating movement to the fingers 45 and finger bar 46 through the intermediary of the pitnan 52.

'I'he length of travel of the fingers may be adjusted by placing the stud 66 into selected holes 52 and 63 to adjust the leverage and throw of the pivot beam 55.

In operation of the mechanism, each of the fingers 45 passes under its respective needle 36 in one direction while such needle is at its topmost position drawing the thread between the needle and the work into a loop about said fingers.

The needle then travels downwardly to take a l stitch, and when it has returned again to its topmost position, the finger 45 passes under the needle in the opposite direction drawing said thread into a second loop about the nger and whereupon another stitch is made. 'Ihe thread forming the finger loops is drawn through the needle eye from the thread supply by thelateral reciprocation of the fingers. 'I'he edges of the slot 35 in the presser' foot through which the needles reciprocate, hold the thread adjacent the top of the work to resist the strain of finger loop formation and prevent tearing of the top cover during the loop forming action of the fingers. The opformation of. loops has been illustrated diagram.l

matically in Figs. 4 to 12-to which reference is now made.

In Figs. 4 to 12 a conventional chain stitch is being formed, modified, however, by our loose stitching mechanism and more particularly by the nnger 45. In Fig. 4 of the drawings, finger loops A and B have already been formed and are.

still disposed over the finger 45. 'I'he needle 35 is just passing downwardly after having formed the finger loop B, and is passing a needle loop M through a looper loopv X on the near side of the looper 4|.

As shown in Fig. 5 the looper 4| then recedes, shedding the needle loop L. In Fig. 6 the looper has advanced again, this time on the other side of the needle, and is passing inside ofv the needle loop M.

As shown in Fig. '7 the needle then passes upwardly and while it is at its topmost position, the finger 45 moves under theneedle preparatory to forming a new finger loop C which is shown in Fig. 8. Here it will be noted that the needle has again traveled downwardly with needle loop N for another stitch. 'I'he needle thus passes again on the near side of the looper 4| inside the looper loop Y.

In Fig. 9 the looper 4| again recedes to shed needle loop M.

Fig. 10 shows the looper 4| again advancing on the near side of the needle to carry the looper loop Z through the needle loop N. l

In Fig. 11 the needle 36 has traveled upwardly once more, leaving the needle loop N around the looper 4|. While the needle is againy in its uppermost position, the finger 45 travels back again under the needle to form a new finger loop D.

The cycle then repeats itself starting with the.

position shown in Fig. 4.

During the operation of the cycle, the work 2l and finger loops pass toward the end of the nger 45-so that they are shed from the ends of the finger as new finger loops are formed. As shown in Fig. 10, the finger loop A has traveled to the end of the finger and is passing off,- and in Fig. 11 the nger loop A has passed completely ol! to lie fiat over the top of the workand hold it in position.

ly and thus prevent the thrust o f the needle4 from pulling up any of the prior finger loops which have been formed.

While the present invention has been illustrated and described particularly in connection with a mechanism for sewing with a double thread chain stitch, it is to be observed that it is adaptable for use in like manner with similar mechanisms using a single thread chain stitch or a lock stitch or the like. 'I'he attachment would work in exactly the same way with other forms of stitches and can be applied to these 'other mechanisms in the same way with the like results.

eration of the stitch forming mechanism and m Modifications and variations may be resorted to within the spirit an'd scope of the present invention as defined in the appended claims.

We claim: l

1. A loose stitching apparatus which comprises a series of needles arranged transversely I the as the latter are withdrawn from the work to draw the thread between the needle and work into aloop about said lingers providing slack for -the loops formed by said needles and hold them in a distended position until the next succeeding series of stitches have been completed, and ad-v justing means for said reciprocating means to adjust the extent of reciprocation of said ringer bar to adjustably vary the length of loops drawn by said ngers. f

2. A loose stitching apparatus which comprises a series of needles arranged transversely of the 'travel of the work to be stitched, loopers individual to each of said needles to coact with said needles to form a series of stitches in said work, a series of fingers individual to each of said nee' dles, said fingers overlying said work and extending longitudinally of the travel of said work,

a linger bar upon which said fingers are mounted, means for reciprocating saidl linger bar and ngers bodily as a unit and thereby causing said lingers' to make passes under said needles as the latter are withdrawn from the work, including a beampivotally mounted intermediate its ends, an articulation between one end of said beam and said finger bar, means at the other end of said beam to oscillate the same, and means for ad- 5 justing the position of said pivot to thereby-vary the length of travel of the finger bar and` lingers.

3. Apparatus for forming a yieldable heatinsulating stitched blanket having substantially planular outer surfaces which comprises a supporting plate ,for the blanket to be stitched, a.

presser `foot spaced from the supporting plate and overlying said blanket in contact therewith and provided with slots extending in the direction of travel of the blanket, a series of reciprocating needles above said presser foot individual to said slots and adapted to pass through said slots to penetrate said blanket, loopers beneath the supporting plate coacting with saidneedles to form stitches, means for feedingy the blanket between said presser footand supporting plate,

,a series of lingers individual to each of said coacting needles and loopers, a linger bar located at the advance side of said needles upon whichthe lingers are mountedsol'ely at their advance ends to extend freely in the direction of travel of the blanket and overlie in spaced relation the upper surface of the-presser foot, a slide on said presser foot in which said nger bar isheld and permitted to reciprocate, and means for recipro-A eating said nger bar and said fingers bodily as a unit to cause the free ends of the lingers to pass under said needles While the needles are withdrawn lfrom the work to draw the thread between the work and needle into a. loop about the v lingers providing slack for the stitches and to hold the loops thus formed in distended position until the succeeding stitches are formed.

HAROLD G. BAILEY. WESTON C. JONES. 

